1. Field of the Invention
The present invention relates to a system for distilling liquid, and more particularly to a vapor collecting type distilling system for distilling seawater at a lower temperature to thereby obtain pure water. The present invention also relates to a method for distilling liquid.
2. Description of the Related Art
Taiwan Utility Model Publication No. 311588 entitled "APPARATUS FOR PURIFYING SEAWATER INTO PURE WATER" issued on Jul. 21, 1997 utilizes an exhaust pipe of the engine and an exhaust pipe of the engine of a generator as well as a condensing device. The condensing device includes an inlet and an outlet for water circulating, a distilling water inlet for pouring, and a condensing tube. The apparatus is characterized in that the exhaust pipe of the vessel engine and the exhaust pipe of the generator engine are enclosed by a metal plate to form a vaporizing device. A separation plate is mounted in the metal plate to separate the exhaust pipe of the vessel engine from the exhaust pipe of the generator engine such that the exhaust pipe of the vessel engine is located in a sealed steam chamber and the exhaust pipe of the generator engine is located in a thermostatic chamber. In addition, a water inlet tube and a steam tube are mounted to an upper part of the steam chamber, wherein one end of the water inlet tube is extended into the steam chamber and associated with the exhaust pipe of the vessel engine, the other end of the water inlet tube is connected to the water inlet of the condensing device, and the steam tube is connected to an end of the condensing tube of the condensing device.
In the above apparatus, water is vaporized in the steam chamber by means of heat generated by the exhaust pipe of the vessel engine. The amount of steam generated and the vaporizing efficiency are both low. In addition, the distilled water cannot be collected reliably since most of the steam condenses and flows back to the steam chamber as a result of arrangement of the water inlet tube rather than enters the steam tube. Furthermore, purification of seawater is proceeded at normal pressure in which the boiling point of water at normal pressure is 100.degree. C., yet the boiling point of seawater is slightly above 100.degree. C. Thus, more energy is required for vaporizing seawater and for condensing the steam. The cost for production pure water is accordingly high.
The present invention is intended to provide an improved distilling system that mitigates and/or obviates the above problems.